c# - 地铁应用程序中的视频捕获

Question

我目前正在使用 Visual Studio Express for Windows 8 IDE 为 windows 8 平板电脑 windows 8 平板电脑开发视频聊天应用程序。我无法使用 MediaCapture 捕获流。我想在 CaptureElement 中捕获视频，然后出于测试目的将其显示在 mediaelement 中。我基本上想将 IRandomAccessStream 转换为字节，然后在 mediaelement 中反之亦然。以下是我的代码：

public sealed partial class MainPage : Page
{

    MediaCapture mediaCapture;
    IRandomAccessStream randomAccessStream;


    public MainPage()
    {
        this.InitializeComponent();
        mediaCapture = new MediaCapture();
        randomAccessStream = new InMemoryRandomAccessStream();

    }


    /// property is typically used to configure the page.</param>
    protected override void OnNavigatedTo(NavigationEventArgs e)
    {

    }


     async private void startCapture(object sender, RoutedEventArgs e)
     {

         await mediaCapture.InitializeAsync();
         capturePreview.Source = mediaCapture;

         MediaEncodingProfile profile = MediaEncodingProfile.CreateWmv(VideoEncodingQuality.Auto);
             await mediaCapture.StartRecordToStreamAsync(profile, randomAccessStream);



     }

     async private void stopCapture(object sender, RoutedEventArgs e)
     {
         await mediaCapture.StopRecordAsync();
         await randomAccessStream.FlushAsync();

         randomAccessStream.Seek(0);

         // want to convert this randomAccessStream into byte[]
         mediaElement.SetSource(randomAccessStream, "video/x-ms-wmv");

     }


}

Answer 1

我已经尝试过下面的代码，它对我来说工作正常。仅在事件中添加代码。

public sealed partial class MainPage : Page
{
    MediaCapture mediaCapture;
    IRandomAccessStream randomAccessStream;
    public MainPage()
    {
        this.InitializeComponent();

        mediaCapture = new MediaCapture();
        randomAccessStream = new InMemoryRandomAccessStream();
    }

    /// <summary>
    /// Invoked when this page is about to be displayed in a Frame.
    /// </summary>
    /// <param name="e">Event data that describes how this page was reached.  The Parameter
    /// property is typically used to configure the page.</param>
    protected override void OnNavigatedTo(NavigationEventArgs e)
    {
    }

    private async void StartButton_Click(object sender, RoutedEventArgs e)
    {
        await mediaCapture.InitializeAsync();

        MediaEncodingProfile profile = MediaEncodingProfile.CreateWmv(VideoEncodingQuality.Auto);
        await mediaCapture.StartRecordToStreamAsync(profile, randomAccessStream);
    }

    private async void StropButton_Click(object sender, RoutedEventArgs e)
    {
        await mediaCapture.StopRecordAsync();
        await randomAccessStream.FlushAsync();

        randomAccessStream.Seek(0);

        // want to convert this randomAccessStream into byte[]
        mediaElement.SetSource(randomAccessStream, "video/x-ms-wmv");
    }
}